DESCRIPTION (Applicant's Description): This program seeks to train investigators at the pre and postdoctoral levels, who will be capable of applying knowledge of basic mechanisms of cellular signal transduction involving cytoskeletal and membrane phenomena to questions of the cell biology of malignant transformation. Formal training courses in both broader aspects of cytoskeletal and membrane organization, and in the biology of cancer, have been developed. These include: (1) Cellular Design Principles: an advanced cell biology course emphasizing developments in cytoskeletal and membrane research. (2) Cancer: A Basic Science Approach: lectures, presentations and related seminars, emphasizing mechanisms of oncogenesis, etiology and mechanisms of treatment of specific cancers. Predoctoral Fellows are required to take these courses. Postdoctoral Fellows are encouraged to audit to supplement their background. A "Cytoskeletal and Malignant Transformation" seminar series, journal clubs, signal transduction research presentations, and retreats form part of the informal training component of this program. Preceptors include a cadre of cancer investigators who interact with basic cell biologists with different technical and programmatic expertise. Preceptor laboratories and trainees concentrate on the cellular signal transduction pathway from external stimulus to molecular and structural response, including basic problems such as cytoskeletal and membrane assembly, activation of motor molecules of the cytoplasm, and protein targeting. Trainees are encouraged to apply such approaches to cancer-related problems such as metastasis, multi-drug resistance and cell growth control. Structural, biochemical, pharmacological, immunological, molecular biological, and genetic approaches are represented by the preceptor laboratories. Fellows in this program are able to experience the diversity of points of view, directed toward common problems at the interface between cell and cancer biology. A steering committee, together with the program director, acts as an executive board for selection of fellows, their reappointments and evaluation of their progress.